PECQ (BE)
Quarry blast1 December 2021
- Magnitude
- 1.7ML
- Depth
- –
- Belgian time
- 12:59:112021-12-01
- UTC
- 11:59:112021-12-01
Main parameters
| Date and time | 2021-12-01 11:59:11 UTC 2021-12-01 12:59:11 Belgian time |
|---|---|
| Magnitude | ML 1.7 |
| Epicentral coordinates | 50.674° N, 3.377° E Uncertainty ± 8.7 km |
| Event ID | ROB 14915 |
Data source : ROB (Royal Observatory of Belgium)
Last update : 2021-12-06 13:51:53 Belgian time
Location map
- Epicentre
- Station that recorded the event
Arrival times at the stations
Each station first records the P wave, the fastest, then the S wave. The farther a station is from the epicentre, the later the waves reach it and the wider the gap between the two.
- Stations
- 8
- Epicentral distance
- 33.2 – 125.4km
- Mean velocity, P wave
- 5.9km/s
- Mean velocity, S wave
- 3.5km/s
- P wave
- S wave
- Curve fitted to the measurements
Notes and method
Curves: travel time of a direct wave in a homogeneous medium. The velocity of each wave and an origin-time shift, common to both, are fitted to the measurements by least squares. Depth not determined: hypocenter placed at the surface for the calculation. P wave: 7 measurements, root-mean-square deviation 0.58 s. S wave: 4 measurements, root-mean-square deviation 0.55 s.
Stations farther than 120 km are left out of the fit: the first waves to reach them have travelled beneath the crust, through the mantle, where they propagate faster.
Station measurements
P- and S-wave arrivals and ground displacement measured at each station. Click a column heading to change the order.
| km | ° | UTC | UTC | s | |
|---|---|---|---|---|---|
| Belgian seismic network (Royal Observatory of Belgium)8 stations | |||||
| LESLessines | 33.2 | 83 | 11:59:17.56+6.53 s | 11:59:21.72+10.69 s | 4.16 |
| SKQSteenkerque | 49.8 | 93 | 11:59:19.58+8.55 s | 11:59:25.39+14.36 s | 5.81 |
| BRQBracquegnies | 57.9 | 112 | 11:59:20.78+9.75 s | – | – |
| RQRRonquières | 60.5 | 97 | 11:59:21.39+10.36 s | – | – |
| SNFSeneffe | 66.7 | 105 | 11:59:21.88+10.85 s | 11:59:29.88+18.85 s | 8.00 |
| MRDMaredsous | 107.0 | 112 | 11:59:29.01+17.98 s | 11:59:42.31+31.28 s | 13.30 |
| DOUDourbes | 108.0 | 126 | 11:59:30.63+19.60 s | – | – |
| GESGesves | 125.4 | 104 | 11:59:32.17+21.14 s | – | – |